Full Auto Friday: 20mm Oerlikon edition (VIDEOS)
By Chris Eger
One of the most iconic anti-aircraft weapons of WWII, the 20mm Oerlikon was ready to swat down kamikaze and Messerschmitt alike.
Back in 1934, the Swiss-based company of Oerlikon Contraves (Oerlikon being the name of the town the factory was located in and contra-aves being Latin for “against birds”) dusted off a World War I design by German arms engineer Reinhold Becker and super-sized it to be able to smoke low-flying aircraft.
This gun, typically just referred to as the Oerlikon, became perhaps one of the most effective single-man operated antiaircraft artillery cannons of the 1940s. And firing a 20x110RB round about three times as heavy as the .50 BMG it’s easy to see why.
A working and transferable Oerlikon on an Mk4 Naval mount. Note the huge recoil spring on the open bolt gun. It was estimated that the gun in U.S. service was responsible for splashing about one out of three Japanese aircraft shot down during WWII. (Photos: Rock Island Auction)
Used by ground forces from Switzerland to Thailand and on everything afloat from PT-boats to battleships and aircraft carriers, the Oerlikon was super popular whenever enemy planes were spotted low on the horizon.
The ammo is in many ways unique today.